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1.
Environ Sci Pollut Res Int ; 30(42): 96617-96628, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37578580

RESUMO

In this study, response surface methodology (RSM) was applied with a Box-Behnken design to optimize the biosorption (removal and bioconcentration) of rare earth elements (REEs) (Y, La, Ce Eu, Gd, Tb) by living Ulva sp. from diluted industrial wastewaters (also containing Pt and the classic contaminants Hg, Pb, Zn, Cu, Co, and Cd). Element concentration (A: 10-190 µg/L), wastewater salinity (B: 15-35), and Ulva sp. dosage (C: 1.0-5.0 g/L) were the operating parameters chosen for optimization. Analysis of the Box-Behnken central point confirmed the reproducibility of the methodology and p-values below 0.0001 validated the developed mathematical models. The largest inter-element differences were observed at 24 h, with most REEs, Cu, Pb and Hg showing removals ≥ 50 %. The factor with the greatest impact (positive) on element removal was the initial seaweed dosage (ANOVA, p < 0.05). The optimal conditions for REEs removal were an initial REEs concentration of 10 µg/L, at a wastewater salinity of 15, and an Ulva sp. dosage of 5.0 g/L, attaining removals up to 88 % in 24 h. Extending the time to 96 h allowed seaweed dosage to be reduced to 4.2 g/L while achieving removals ≥ 90 %. The high concentrations in REE-enriched biomass (∑REEs of 3222 µg/g), which are up to 3000 times higher than those originally found in water and exceed those in common ores, support their use as an alternative source of these critical raw materials.


Assuntos
Mercúrio , Metais Terras Raras , Alga Marinha , Ulva , Poluentes Químicos da Água , Águas Residuárias , Chumbo/análise , Reprodutibilidade dos Testes , Poluentes Químicos da Água/análise , Mercúrio/análise
2.
J Hazard Mater ; 445: 130405, 2023 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-36437192

RESUMO

Mercury (Hg) is a global and top priority contaminant, toxic at low concentrations. Although it has been progressively eliminated from processes, this metal continues to circulate in the atmosphere, soil, and water. In this work, the Response Surface Methodology (RSM) combined with a Box-Behnken Design (3 factors - 3 levels) was used to optimize key operational conditions that influence the removal and uptake of Hg by living macroalga Ulva sp. in a complex mixture containing several elements used in industry (potentially toxic elements, rare earth elements, and platinum-group elements) (initial concentration 10, 100 and 190 µg/L, salinity 15, 25 and 35, seaweed stock density 1.0, 3.0 and 5.0 g/L). Results evidenced the great capability of Ulva sp. to remove Hg, with removal efficiencies between 69 % and 97 %. 3-D surfaces showed that the most impactful variable was seaweed stock density, with higher densities leading to higher removal. Regarding the uptake, a positive correlation between initial concentration and qt values was observed. The appliance of RSM made possible to obtain optimal operating conditions for removing virtually 100 % of Hg from waters with high ionic strength, which is a pivotal step in the direction of the application of this remediation biotechnology at large scale.


Assuntos
Mercúrio , Metais Terras Raras , Alga Marinha , Ulva , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Salinidade
3.
Food Chem ; 404(Pt B): 134669, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36323022

RESUMO

To routinely assess whether consumed food meets international guidelines, a single analytical method able to quantify minerals and potentially toxic elements (PTEs) in real food matrices is required. This work validated a simple and efficient method to quantify nine elements in different food matrices by ICP-MS. Samples from local markets (chicken, mussels, fish, rice, and seaweed) and certified reference materials were digested with HNO3 68 % and H2O2 30 %. All performance criteria (working range, linearity, LOD, LOQ, selectivity, repeatability, and trueness) met the requirements of the Portuguese Association of Accredited Laboratories. Comparison between raw and cooked food showed significant changes in most element levels, and PTEs contents complied with the maximum permissible values (EC N° 1881/2006). The minimum and maximum amounts of the foods studied, alone or in combination, raw or cooked, that can be daily consumed to meet EFSA and WHO nutritional and safety requirements were analysed.


Assuntos
Oryza , Oligoelementos , Animais , Peróxido de Hidrogênio , Alimentos , Minerais , Análise Espectral , Oligoelementos/análise
4.
Int J Biometeorol ; 67(1): 133-148, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36474028

RESUMO

Due to global climate change, droughts are likely to become more frequent and more severe in many regions such as in South Africa. In Limpopo, observed high climate variability and projected future climate change will likely increase future maize production risks. This paper evaluates drought patterns in Limpopo at two representative sites. We studied how drought patterns are projected to change under future climatic conditions as an important step in identifying adaptation measures (e.g., breeding maize ideotypes resilient to future conditions). Thirty-year time horizons were analyzed, considering three emission scenarios and five global climate models. We applied the WOFOST crop model to simulate maize crop growth and yield formation over South Africa's summer season. We considered three different crop emergence dates. Drought indices indicated that mainly in the scenario SSP5-8.5 (2051-2080), Univen and Syferkuil will experience worsened drought conditions (DC) in the future. Maize yield tends to decline and future changes in the emergence date seem to impact yield significantly. A possible alternative is to delay sowing date to November or December to reduce the potential yield losses. The grain filling period tends to decrease in the future, and a decrease in the duration of the growth cycle is very likely. Combinations of changed sowing time with more drought tolerant maize cultivars having a longer post-anthesis phase will likely reduce the potential negative impact of climate change on maize.


Assuntos
Secas , Zea mays , África do Sul , Mudança Climática , Grão Comestível , Agricultura
5.
J Rheumatol ; 49(12): 1390-1394, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36243405

RESUMO

OBJECTIVE: Immunoglobulin A vasculitis (IgAV) usually occurs following viral respiratory tract infection. In the context of the global coronavirus disease 2019 (COVID-19) pandemic, we describe a case series of patients who developed IgAV following SARS-CoV-2 infection. METHODS: This national multicenter retrospective study included patients with IgAV following SARS-CoV-2 infection from January 1, 2020, to January 1, 2022. Patients had histologically proven IgAV and reverse transcription PCR (RT-PCR)-proven SARS-CoV-2 infection. The interval between infection and vasculitis onset had to be < 4 weeks. RESULTS: We included 5 patients, 4 of whom were women with a mean age of 45 years. Four patients had paucisymptomatic infections and 1 required a 48-hour low-flow oxygen treatment. All 5 patients had purpuric skin involvement. Arthritis was observed in 2 patients, 3 had IgA glomerulonephritis, and 2 had digestive involvement. Three renal biopsies were performed and showed mesangial IgA deposits without any extracapillary proliferation. Median C-reactive protein was 180 (range 15.1-225) mg/L, median serum creatinine level was 65 (range 41-169) µmol/L, and 2 patients had a glomerular filtration rate < 60 mL/min. Four patients received first-line treatment with glucocorticoids. All patients had a favorable progression and 2 patients experienced minor skin relapses, one after COVID-19 vaccination. CONCLUSION: This series describes the emergence of IgAV closely following COVID-19; we were not able to eliminate an incidental link between these events. Their disease outcomes were favorable. In most of our patients, the SARS-CoV-2 infection was paucisymptomatic, and we recommend RT-PCR tests to look for COVID-19 in patients without any evident triggers for IgAV.


Assuntos
COVID-19 , Vasculite por IgA , Vasculite , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , COVID-19/complicações , Estudos Retrospectivos , SARS-CoV-2 , Vacinas contra COVID-19 , Imunoglobulina A
6.
Acta Paul. Enferm. (Online) ; 35: eAPE01456, 2022. tab
Artigo em Português | LILACS, BDENF - Enfermagem | ID: biblio-1393723

RESUMO

Resumo Objetivo Avaliar o impacto do programa de comanejo multidisciplinar nos desfechos de pacientes com fratura de quadril hospitalizados. Métodos Estudo observacional, do tipo antes e depois, retrospectivo. Foram coletados dados dos pacientes hospitalizados por fratura de quadril entre 2015 e 2019, em hospital universitário com serviço referência para ortopedia. A intervenção analisada foi o programa de comanejo multidisciplinar, que iniciou em 2017. Resultados O número de lesões por pressão adquiridas na internação diminuiu significativamente (p<0,005) após a implementação do comanejo. Da mesma forma, o tempo de internação até a cirurgia reduziu (p<0,046), sendo cumpridas as diretrizes nacionais e internacionais de correção da fratura em até 48 horas. Infecções, reinternações e óbitos não tiveram seu impacto confirmado. Conclusão O comanejo multidisciplinar teve impacto positivo nos desfechos dos pacientes hospitalizados por fratura de quadril, resultando em redução do número de lesões por pressão e do tempo de espera para realizar a cirurgia. Através deste estudo, foram identificadas evidências preliminares que suportam a implementação desse tipo de programa.


Resumen Objetivo Evaluar el impacto del programa de manejo conjunto multidisciplinario en los desenlaces de pacientes con fractura de cadera hospitalizados. Métodos Estudio observacional, tipo antes y después, retrospectivo. Se recopilaron datos de pacientes hospitalizados por fractura de cadera entre 2015 y 2019, en un hospital universitario con servicio de ortopedia de referencia. La intervención analizada fue el programa de manejo conjunto multidisciplinario, que comenzó en 2017. Resultados El número de úlceras por presión adquiridas en la internación se redujo significativamente (p<0,005) luego de la implementación del manejo conjunto. De la misma forma, el tiempo de internación hasta la cirugía se redujo (p<0,046), cumpliendo las directrices nacionales e internacionales de corrección de la fractura en 48 horas como máximo. No se confirmó el impacto de infecciones, reinternaciones y fallecimientos. Conclusión El manejo conjunto multidisciplinario tuvo un impacto positivo en los desenlaces de los pacientes hospitalizados por fractura de cadera, lo que redujo el número de úlceras por presión y el tiempo de espera para realizar la cirugía. A través de este estudio, se identificaron evidencias preliminares que respaldan la implementación de este tipo de programa.


Abstract Objective To assess the impact of the multidisciplinary co-management program on the outcomes of hospitalized patients with hip fractures. Methods This is an observational, before-and-after, retrospective study. Data were collected from patients hospitalized for hip fracture between 2015 and 2019, at a university hospital with a referral service for orthopedics. The intervention analyzed was the multidisciplinary co-management program, which started in 2017. Results The number of pressure injuries acquired during hospitalization decreased significantly (p<0.005) after the implementation of co-management. Likewise, the length of hospital stay until surgery was reduced (p<0.046), and national and international guidelines for fracture correction within 48 hours were complied with. Infections, readmissions and deaths have not had their impact confirmed. Conclusion The multidisciplinary co-management had a positive impact on the outcomes of patients hospitalized for hip fracture, resulting in a reduction in the number of pressure injuries and in the waiting time for surgery. Through this study, preliminary evidence was identified to support the implementation of this type of program.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Equipe de Assistência ao Paciente , Enfermagem Ortopédica , Registros Eletrônicos de Saúde , Fraturas do Quadril , Hospitalização , Estudos Retrospectivos , Estudos Observacionais como Assunto , Tempo de Internação
7.
J Environ Manage ; 300: 113697, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34543961

RESUMO

Dysprosium (Dy) is a rare earth element with a high economic and strategic value, and simultaneously an emerging contaminant, whose removal from wastewaters is gaining increasing attention. In this work, the Response Surface Methodology (RSM) combined with a Box-Behnken Design (3 factors-3 levels) was used to optimize the key operational conditions that influence the uptake of Dy by two living seaweed, Ulva sp. and Gracilaria sp.. The initial concentration of Dy (10-500 µg/L), water salinity (10-30), and seaweed dosage (0.5-5.5 g/L) were the independent variables, while the removal efficiency (%) and bioaccumulation (q, µg/g) were the response variables. Results highlighted the high capacity of both species to capture Dy. After 168 h, the optimal conditions that led to a maximum of 91 % of Dy removed by Gracilaria sp. were: 500 µg of Dy per L of water, salinity 10, and 5.5 g of seaweed per L. For Ulva sp., a maximum removal percentage of 79 % was achieved in the conditions: any initial concentration of Dy, salinity 20, and seaweed dosage of 3.7 g/L. Independently of the species, the response surfaces showed that the most important variable for the removal is the seaweed dosage, while for bioaccumulation is the initial concentration of Dy. Using RSM, it was possible to obtain the optimal operating conditions for Dy removal from waters, which is a fundamental step toward the application of the proposed technology at large scale.


Assuntos
Alga Marinha , Ulva , Poluentes Químicos da Água , Disprósio , Água , Poluentes Químicos da Água/análise
8.
Sci Total Environ ; 786: 147176, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-33971602

RESUMO

Europium (Eu) strategic importance for the manufacturing industry, high economic value and high supply risk, categorizes it as critical raw material. Due to anthropogenic contamination, Eu levels in ecosystems have been growing, which opens opportunities for innovation: its recovery and recycling from contaminated water as element source - circular economy. In this pioneering study, six widely available living marine macroalgae (Ulva intestinalis, Ulva lactuca, Gracilaria sp., Osmundea pinnatifida, Fucus vesiculosus and Fucus spiralis) were characterized (water content and specific surface area) and evaluated in the pre-concentration and recovery of Eu from contaminated seawater, under different relevant contamination scenarios (10, 152 and 500 µg L-1). U. lactuca and Gracilaria sp. (3 g L-1, fresh weight) proved to be the most effective in removing Eu, reaching up to 85% in 72 h, while the highest Eu enrichment was observed in U. intestinalis biomass, up to 827 µg g-1 (bioconcentration factor of 1800), which is higher than Eu levels in common apatite ores. The effect of Eu exposure on macroalgae growth rate and organism biochemical performance (LPO, SOD, GPx and GSTs) was also evaluated for the first time, to the best of our knowledge. Although no cellular damage was recorded, findings revealed toxicity and defence mechanisms activation, emphasizing the need of further studies on the potential risks associated with the presence of this emerging contaminant in aquatic ecosystems.


Assuntos
Alga Marinha , Ulva , Poluentes Químicos da Água , Ecossistema , Európio , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Poluição da Água
9.
Chemosphere ; 280: 130600, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33940453

RESUMO

The high demand for greener energy and technological innovation require some crucial elements, such as the rare earths Nd and Dy. Being considered two of the most critical elements (high supply risk), it is vital to recover them from wastes/wastewaters, for later reuse. Here, the influence of operational parameters, such as biosorbent stock density (0.5, 3.0, and 5.5 g L-1), ionic strength (salinity 10 and 30) and contact time (24, 72 and 168 h), in the biosorption/bioaccumulation of Nd and Dy by two living marine macroalgae was evaluated in artificial seawater, seeking the improvement of the process. Results demonstrated that stock density is the most influential parameter, while the ionic strength showed to be a selective parameter, with a major influence only for Dy removal, which can be attributed to the different chemical characteristics observed between light rare earth elements (LREE) and heavy rare earth elements (HREE). For the ranges studied, the greatest removal/recovery for Gracilaria sp. was achieved with a stock density of 3.0 g L-1 at salinity 10, after 72 h for both REEs. For Ulva lactuca optimal conditions were: stock density of 5.5 g L-1 at salinity 10 with a contact time of 72 h for both REEs. Between species, U. lactuca showed to be the most promising, with removal efficiencies up to 98% for Nd and 89% for Dy. Findings substantiate the potential of the proposed process for obtaining Nd and Dy from secondary sources, particularly from low-level contaminated waters.


Assuntos
Metais Terras Raras , Alga Marinha , Ulva , Poluentes Químicos da Água , Disprósio , Neodímio , Poluentes Químicos da Água/análise
10.
Environ Sci Pollut Res Int ; 28(23): 30255-30266, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33586107

RESUMO

Mercury is a very toxic metal that persists and accumulates in the living organisms present in the aquatic systems and its elimination is an urgent need. Two green (Ulva intestinalis and Ulva lactuca), brown (Fucus spiralis and Fucus vesiculosus), and red (Gracilaria sp. and Osmundea pinnatifida) marine macroalgae were tested for mercury removal from saline waters. The ability of each species was evaluated to the initial mercury concentrations of 50, 200, and 500 µg dm-3 along 72 h. In general, all species exhibited good performances, removing 80.9-99.9% from solutions with 50 µg dm-3, 79.3-98.6% from solutions with 200 µg dm-3, and 69.8-97.7% from solutions containing 500 µg dm-3 of mercury. Among the macroalgae, Ulva intestinalis showed the highest affinity to mercury and it presented an uptake ability up to 1888 µg g-1 of Hg(II) and bioconcentration factors up to 3823, which proved its promising potential on Hg removal.


Assuntos
Mercúrio , Alga Marinha , Ulva , Poluentes Químicos da Água , Bioacumulação , Águas Salinas , Poluentes Químicos da Água/análise
11.
Int J Biometeorol ; 65(7): 1001-1013, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33555405

RESUMO

The influence of climate conditions in the agricultural environment is important in evapotranspiration, water availability for plants and roots, and other processes. This research focuses on two aspects: (1) the effects of climate change on the occurrence of extreme events that may affect agricultural processes in a region in Illinois (USA), and (2) the effects of climate change on the soil water dynamics in a corn crop. Different climate scenarios developed by the Institut Pierre Simon Laplace, using a climate model with medium resolution-IPSL(CM5MR), provided input to simulate soil water dynamics in two fields with different drainage system layouts. The Hydrus model simulated surface flux and runoff. Results indicate that the variation of precipitation and temperature in the future may increase extreme events, representing a risk for agriculture. Hydrus simulations indicate different results accordingly to the drainage layout, suggesting that it may be necessary to make adjustments in drainage systems in the future. In general, surface flux and runoff will increase over time, and these changes are more related to extreme events than average values. Extreme event indices show vulnerability in agriculture and will be reflected in changes in the soil water dynamics, and may increase the climatic risk of corn production.


Assuntos
Mudança Climática , Solo , Agricultura , Illinois , Água , Zea mays
12.
Acta Histochem ; 123(2): 151678, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33434858

RESUMO

Mucopolysaccharidosis type I (MPS I) is a lysosomal storage disorder characterized by alpha-L-iduronidase (IDUA) deficiency, an enzyme responsible for glycosaminoglycan degradation. Musculoskeletal impairment is an important component of the morbidity related to the disease, as it has a major impact on patients' quality of life. To understand how this disease affects bone structure, morphological, biomechanical and histological analyses of femurs from 3- and 6-month-old wild type (Idua +/+) and MPS I knockout mice (Idua -/-) were performed. Femurs from 3-month-old Idua -/- mice were found to be smaller and less resistant to fracture when compared to their age matched controls. In addition, at this age, the femurs presented important alterations in articular cartilage, trabecular bone architecture, and deposition of type I and III collagen. At 6 months of age, femurs from Idua -/- mice were more resistant to fracture than those from Idua +/+. Our results suggest that the abnormalities observed in bone matrix and articular cartilage in 3-month-old Idua -/- animals caused bone tissue to be less flexible and more likely to fracture, whereas in 6-month-old Idua -/- group the ability to withstand more load before fracturing than wild type animals is possibly due to changes in the bone matrix.


Assuntos
Iduronidase/metabolismo , Mucopolissacaridose I/metabolismo , Mucopolissacaridose I/patologia , Animais , Fenômenos Biomecânicos/fisiologia , Colágeno/metabolismo , Modelos Animais de Doenças , Feminino , Fêmur/enzimologia , Fêmur/metabolismo , Fêmur/patologia , Iduronidase/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mucopolissacaridose I/enzimologia
13.
Food Chem ; 343: 128438, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33127231

RESUMO

Concentrations of 16 elements (K, Na, Mg, Ca, Fe, Zn, Hg, Se, As, Cu, Cd, Mn, Ni, Cr, Pb and Co) were determined in dorsal white and dark muscle of Xiphias gladius, sampled at various positions of a single swordfish and at the same position of eight specimens. Hg was quantified by thermal decomposition atomic absorption spectrometry (LECO AMA-254) and the rest of the elements by inductively coupled plasma optical emission spectrometry (ICP OES) or mass spectrometry (ICP MS). Element partitioning differed in dark and white muscle. Dark muscle was particularly enriched in Fe (median 13 times) and Cu (9) and moderately enhanced in Se, Mn, Zn and Cd (2.8-4.0). Dark:white ratios of the potentially toxic elements (As, Cr, Hg, Ni and Pb) varied from 0.9 to 1.4, pointing to a similar distribution between the two muscles types and indicating no additional risk in the consumption of dark muscle.


Assuntos
Produtos Pesqueiros/análise , Músculo Esquelético/química , Perciformes , Oligoelementos/análise , Poluentes Químicos da Água/análise , Animais , Contaminação de Alimentos/análise , Oceano Índico , Espectrometria de Massas/métodos , Espectrofotometria Atômica
14.
Tuberculosis (Edinb) ; 126: 102043, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33370646

RESUMO

Although treatable with antibiotics, tuberculosis is a leading cause of death. Mycobacterium tuberculosis antibiotic resistance is becoming increasingly common and disease control is challenging. Conventional drug susceptibility testing takes weeks to produce results, and treatment is often initiated empirically. Therefore, new methods to determine drug susceptibility profiles are urgent. Here, we used mass-spectrometry-based metabolomics to characterize the metabolic landscape of drug-susceptible (DS), multidrug-resistant (MDR) and extensively drug-resistant (XDR) M. tuberculosis. Direct infusion mass spectrometry data showed that DS, MDR, and XDR strains have distinct metabolic profiles, which can be used to predict drug susceptibility and resistance. This was later confirmed by Ultra-High-Performance Liquid Chromatography and High-Resolution Mass Spectrometry, where we found that levels of ions presumptively identified as isoleucine, proline, hercynine, betaine, and pantothenic acid varied significantly between strains with different drug susceptibility profiles. We then confirmed the identification of proline and isoleucine and determined their absolute concentrations in bacterial extracts, and found significantly higher levels of these amino acids in DS strains, as compared to drug-resistant strains (combined MDR and XDR strains). Our results advance the current understanding of the effect of drug resistance on bacterial metabolism and open avenues for the detection of drug resistance biomarkers.


Assuntos
Antituberculosos/farmacologia , Tuberculose Extensivamente Resistente a Medicamentos/metabolismo , Metaboloma/fisiologia , Metabolômica/métodos , Mycobacterium tuberculosis/metabolismo , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação
15.
Environ Pollut ; 267: 115458, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33254618

RESUMO

Considering the increasing use of Lithium (Li) and the necessity to fulfil this demand, labile Li occurrence in the environment will be enhanced. Thus, additional research is needed regarding the presence of this element in marine environment and its potential toxic impacts towards inhabiting wildlife. The aim of the present study was to evaluate Li toxicity based on the exposure of Mytilus galloprovincialis to this metal, assessing the biochemical changes related with mussels' metabolism, oxidative stress and neurotoxicity. For this, organisms were exposed to different Li concentrations (100, 250, 750 µg/L) for 28 days. The results obtained clearly demonstrated that Li lead to mussels' metabolism depression. The present study also revealed that, especially at the highest concentrations, antioxidant and biotransformation enzymes were not activated, leading to the occurrence of lipid peroxidation and loss of redox homeostasis, with increased content in oxidized glutathione in comparison to the reduced form. Furthermore, after 28 days, higher Li exposure concentrations induced neurotoxic effects in mussels, with a decrease in acetylcholinesterase enzyme activity. The responses observed were closely related with Li concentrations in mussels' tissues, which were more pronounced at higher exposure concentrations. Such results highlight the potential toxic effects of Li to marine species, which may even be higher under predicted climate changes and/or in the presence of other pollutants.


Assuntos
Mytilus , Poluentes Químicos da Água , Animais , Animais Selvagens , Biomarcadores , Dissulfeto de Glutationa , Peroxidação de Lipídeos , Lítio/toxicidade , Estresse Oxidativo , Fenômenos Físicos , Poluentes Químicos da Água/toxicidade
16.
Environ Pollut ; 266(Pt 1): 115374, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32841840

RESUMO

Potentially toxic elements (PTEs) are of major concern due to their high persistence and toxicity. Recently, rare earth elements (REEs) concentration in aquatic ecosystems has been increasing due to their application in modern technologies. Thus, this work aimed to study, for the first time, the influence of REEs (lanthanum, cerium, praseodymium, neodymium, europium, gadolinium, terbium, dysprosium and yttrium) and of salinity (10 and 30) on the removal of PTEs (Cd, Cr, Cu, Hg, Ni and Pb) from contaminated waters by living macroalgae (Fucus spiralis, Fucus vesiculosus, Gracilaria sp., Osmundea pinnatifida, Ulva intestinalis and Ulva lactuca). Experiments ran for 168 h, with each macroalga exposed to saline water spiked with the six PTEs and with the six PTEs plus nine REEs (all at 1 µmol L-1) at both salinities. Results showed that all species have high affinity with Hg (90-99% of removal), not being affected neither by salinity changes nor by the presence of other PTEs or REEs. Cd showed the lowest affinity to most macroalgae, with residual concentrations in water varying between 50 and 108 µg L-1, while Pb removal always increased with salinity decline (up to 80% at salinity 10). REEs influence was clearer at salinity 30, and mainly for Pb. No substantial changes were observed in Ni and Hg sorption. For the remaining elements, the effect of REEs varied among algae species. Overall, the results highlight the role of marine macroalgae as living biofilters (particularly U. lactuca), capable of lowering the levels of top priority hazardous substances (particularly Hg) and other PTEs in water, even in the presence of the new emerging contaminants - REEs. Differences in removal efficiency between elements and macroalgae are explained by the contaminant chemistry in water and by macroalgae characteristics.


Assuntos
Mercúrio , Alga Marinha , Poluentes Químicos da Água/análise , Cádmio , Ecossistema , Chumbo , Salinidade
17.
Sci Total Environ ; 749: 141488, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-32829275

RESUMO

Gadolinium (Gd) is a rare earth associated with hospital and urban wastewaters due to its application as a contrast agent for magnetic resonance imaging. In this work, the uptake of Gd from contaminated seawater by three living marine macroalgae, Ulva lactuca (Chlorophyta), Fucus spiralis (Phaeophyta) and Gracilaria sp. (Rhodophyta) was studied along 72 h. Surface analysis (FTIR), water content, kinetic modelling, and Gd quantification in seawater and biomass were performed. All species were able to accumulate Gd from seawater with 10, 157, and 500 µg Gd L-1, although green and red macroalgae performed better, following the order: green > red > brown. Removal efficiencies reached 85%, corresponding to a bioconcentration factor of 1700. In more complex solutions that intended to mimic real contaminated environments, namely mixtures with other rare earth elements (Y, La, Ce, Pr, Nd, Eu, Tb, Dy), and with potentially toxic elements commonly found in wastewaters (Cr, Ni, Cu, Cd, Hg, Pb), at two salinities (10 and 30), the macroalgae kept its efficiency: 84% and 88% of removal by green and red macroalgae, respectively. Overall, findings evidence that living macroalgae could be a countermeasure to the increasing anthropogenic enrichment of Gd observed in the aquatic environment.


Assuntos
Mercúrio , Alga Marinha , Ulva , Poluentes Químicos da Água , Gadolínio , Poluentes Químicos da Água/análise
18.
Environ Pollut ; 264: 114711, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32559867

RESUMO

Myctophids are the most abundant fish group in the Southern Ocean pelagic ecosystem and are an important link in the Antarctic marine food web. Due to their major ecological role, evaluating the level of mercury (Hg) contamination in myctophids is important as a step towards understanding the trophic pathway of this contaminant. The concentrations of total Hg were determined in muscle, gill, heart and liver tissue of 9 myctophid species to quantify tissue partitioning variability between species. Organic Hg concentration and proportion in muscle was also determined. Hg concentrations were higher in the liver and heart than in muscle and gills, but the proportion of organic Hg was almost 100% in muscle, indicating that the main uptake route for Hg is through the diet. Most of the species analysed have similar vertical and horizontal distributions, and similar feeding modes and prey. Geographical and temporal variability of Hg concentrations was examined using samples from 3 different sampling cruise (2007/08, 2015/16 and 2016/17) and 2 locations (South Georgia and South Orkneys Islands). Our results appear to indicate a decreasing trend in Hg contamination over the last decade, particularly gill tissue, which is in agreement with a previous study on squid from the same region. There was no significant variability in Hg concentration between the different sampling locations. Hg levels were consistent with values reported previously for myctophids around the world, indicating low global-scale geographic variability. A positive relationship between fish size and Hg concentration was found for most species, with the exception of Electrona antarctica females, which may be explained through Hg elimination by egg laying. We estimate that myctophids collectively comprise a Southern Ocean mercury 'reserve' of ≈1.82 metric tonnes.


Assuntos
Mercúrio/análise , Poluentes Químicos da Água/análise , Animais , Regiões Antárticas , Ecossistema , Monitoramento Ambiental , Feminino , Peixes , Cadeia Alimentar , Ilhas , Oceanos e Mares
19.
Int J Biometeorol ; 64(7): 1051-1062, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32166442

RESUMO

In the face of climate change scenarios, it is important to evaluate the possibility of an increase in the incidence of corn crop diseases and to promote studies aimed at creating mitigation measures. This paper aims to study the impacts that regional climate changes may have on the potential occurrence of corn common rust (Puccinia sorghi), in the region of Castro, Paraná (Brazil). The Eta climate model was driven by the global model CanESM2. We use the Historical simulation of the EtaCanESM2 model from 1981 to 2005, and future projections from 2046 to 2070 to simulate the occurrence of common rust. The criteria was adopted to simulate the common rust disease favored in environments with the minimum temperature lower than 8 °C, the maximum temperature higher than 32 °C, average temperature between 16 and 23 °C, and relative humidity higher than 95%. In Brazil, there are two different seasons for corn crop (Normaland Safrinha). Results show that relative humidity and minimum temperature simulated by the model presented good skills, approaching the observed data. Compared to the Historical simulation, the projections show a tendency to increase of maximum and minimum temperature in the future, and a tendency to decrease relative humidity. There is an increase in the number of days with the potential for the occurrence of the disease. The distribution of days with favorable conditions to rust disease tends to change in the future. In the Normaland Safrinhaseasons, there is a tendency to increase the number of days with favorable conditions to common rust occurrence. The influence of planting time is greater in Historical simulation when compared to future scenarios. The Safrinhaseason may present more days with the potential for the occurrence of common rust in the future than the Normalseason.


Assuntos
Basidiomycota , Zea mays , Brasil , Mudança Climática , Produtos Agrícolas
20.
Joint Bone Spine ; 86(2): 211-217, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30053612

RESUMO

OBJECTIVE: To evaluate the performance of salivary gland ultrasonography for the diagnosis of primary and secondary Sjögren's syndromes (pSS and sSS). METHOD: Multicenter cross-sectional study on 97 patients with clinical sicca symptoms. The pSS (n = 22) met the American-European Consensus Group (AECG) classification criteria. The control patients (n = 36) with sicca symptoms did not fulfill the AECG criteria. Four scores were used to evaluate the 4 major salivary gland echostructure: the Salaffi score (0-16), Jousse-Joulin score (0-4), Hocevar score (0-48) and Milic score (0-12). RESULTS: The medians of ultrasonographic (US) scores were higher in the pSS and sSS groups than in the control group (P < 0.001). The receiver-operating characteristic (ROC) curves and the positive likelihood ratio (LR+) of the four scores showed a good diagnostic performance for the US diagnosis of pSS and sSS. Respectively, for pSS and sSS, the AUC were 0.891 (95%CI 0.812-0.970) and 0.824 (95%CI 0.695-0.954) for Hocevar score, 0.885 (95%CI 0.804-0.965) and 0.808 (95%CI 0.673-0.943) for Milic score, 0.915 (95%CI 0.848-0.982) and 0.844 (95%CI 0.724-0.965) for Salaffi score, 0.897 (95%CI 0.821-0.973) and 0.851 (95%CI 0.735-0.968) for Jousse-Joulin score. This study showed an interesting inter-observer reproducibility (kappa = 0.714 ± 0.131) of the US evaluation with 85.7% agreement between reader to determine the pathological character of the salivary glands. CONCLUSION: Salivary gland US is a simple, non-invasive and performant imaging procedure for the diagnosis of pSS and sSS, with Salaffi, Milic and Jousse-Joulin scores.


Assuntos
Glândulas Salivares/diagnóstico por imagem , Síndrome de Sjogren/diagnóstico por imagem , Síndrome de Sjogren/patologia , Ultrassonografia Doppler/métodos , Adulto , Área Sob a Curva , Distribuição de Qui-Quadrado , Estudos Transversais , Feminino , França , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Glândulas Salivares/patologia , Sensibilidade e Especificidade , Índice de Gravidade de Doença
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